It happened just before 7 a.m. at Utica Avenue near Kettleman City.
The cause of the crash is unclear at this time. Traffic was reported to be backed up for about mile.
CHP officials say drivers should expect delays.
Interstate 5: Northbound I-5 at Utica Avenue near Kettleman City, solo overturned big rig blocking all lanes. Traffic back up is 1/2 mile. Expect delays, no ETO. pic.twitter.com/wQwnKmlYBV— Caltrans District 6 (@CaltransDist6) May 5, 2020